1. Field of the Invention
The present invention generally relates to a semiconductor device and a manufacturing method thereof and, more particularly, to a semiconductor device and a manufacturing method thereof which device provides a three-dimensional structure so as to increase a packaging density thereof.
As an electronic apparatus becomes smaller in size, weight and thickness, a semiconductor device used in such an electronic apparatus is required to be smaller in size and thickness. In an attempt to satisfy these requirements, the trend of a semiconductor device package has been shifting from a QFP (Quad Flat Package) for surface mounting in which package terminals are led out in four directions in the shape of a gull wing, to a BGA (Ball Grid Array) having external connection terminals arranged on the bottom of a package in the form of an area array, or to a CSP (Chip Size Package).
Among semiconductor packages like these, a package of a fan-out type is widely used, in which package a semiconductor chip is mounted on a wiring substrate (an interposer) and external connection terminals are arranged around the semiconductor chip by the interposer.
2. Description of the Related Art
FIG. 1 is a cross-sectional view of a conventional semiconductor device of the fan-out type. In FIG. 1, a semiconductor device 1 mainly comprises a substrate 2, a semiconductor chip 4, solder balls (bumps) 6, and a sealing resin 8. The substrate 2, electrode patterns 10 and a bonding pad 12 compose an interposer. The interposer is used to electrically connect an external electrode and the semiconductor chip 4.
The substrate 2 is formed of such a material as a polyimide resin, a ceramic resin, and a glass-epoxy resin. The substrate 2 has the semiconductor chip 4 mounted on a surface 2a thereof and also has the electrode patterns 10 formed on the surface 2a. The semiconductor chip 4 is fixed faceup on the substrate 2 by a DB material (a bonding pad) 5. The electrode patterns 10 are provided by applying a copper film on the substrate 2 and forming the copper film into predetermined patterns by, for example, etching. The electrode patterns 10 are electrically connected to each other by wiring patterns not shown in the figures.
Some of the electrode patterns 10 are consolidated with the bonding pad 12. The bonding pad 12 and an electrode of the semiconductor chip 4 are connected by a wire 14. Thereby, the semiconductor chip 4, the electrode patterns 10 and the bonding pad 12 are electrically connected via the wire 14 and the wiring patterns. The surface 2a of the substrate 2 is sealed by the sealing resin 8 formed of such a material as an epoxy resin so as to protect the semiconductor chip 4, the wire 14, the bonding pad 5, and the other elements formed on the surface 2a. 
Further, a hole 16 penetrating through the substrate 2 is formed at a position facing each of the electrode patterns 10. The hole 16 is formed by processing the substrate 2 by a laser, a drill or a metal mold, etc.
The solder balls 6 are arranged toward a back surface 2b of the substrate 2. Each of the solder balls 6 is placed into the hole 16, and is joined to the electrode pattern 10 through the hole 16. That is, each of the solder balls 6 is fixed to the substrate 2 by being fixed to the electrode pattern 10.
As described above, a package structure using an interposer in the semiconductor device 1 has been becoming a mainstream of a semiconductor device package. However, as a semiconductor device has been made to have an even higher density, a packaging area in a semiconductor package including a semiconductor chip has been becoming smaller. Accordingly, a package size of a semiconductor device is made smaller to the extent that a two-dimensional miniaturization of a package structure is supposedly reaching the limit. Therefore, to realize a further miniaturization of a semiconductor device, a three-dimensional (stack) packaging is required. As an example of the three-dimensional packaging, a semiconductor device having connection electrodes on the upper surface of a resin package is provided.
However, in order to provide connection electrodes on the upper surface of a resin package as mentioned above, wires have to be arranged around the resin package, making it difficult to provide the connection electrodes out on the upper surface of the resin package. For example, in a case where a wire connected to an external terminal formed on an interposer is led to the upper surface of the resin package after the formation thereof by being detoured around the outer surface of the semiconductor device so as to avoid the resin package, the wire becomes exposed and thus is likely to be cut, which impairs the reliability of the semiconductor device. Additionally, with this manner of arranging the connection electrodes, the wires become long so as to increase the impedance thereof, making it difficult for the semiconductor device to operate at high speed.
It is a general object of the present invention to provide an improved and useful semiconductor device and a manufacturing method thereof in which device the above-mentioned problems are eliminated.
A more specific object of the present invention is to provide a semiconductor device and a manufacturing method thereof which device can be stacked on one another to form a semiconductor device package having a simple three-dimensional structure so as to increase a packaging density thereof.
In order to achieve the above-mentioned objects, there is provided according to one aspect of the present invention a semiconductor device comprising:
a first semiconductor element;
an external terminal used for an external connection;
an interposer having the first semiconductor element mounted on a first surface thereof and having the external terminal formed on a second surface thereof opposite to the first surface so as to electrically connect the first semiconductor element and the external terminal;
a resin sealing the first semiconductor element on the first surface; and
an interconnecting portion formed within the resin, the interconnecting portion having a first connecting part electrically connected to the external terminal and having a second connecting part exposed on an outer surface of the resin.
According to the present invention, the interconnecting portion electrically connects the external terminal and an external terminal of another semiconductor device of the same type contacting the second connecting part so that a plurality of the semiconductor devices of the same type can be stacked. That is, the interconnecting portion enables stacking and combining a plurality of the semiconductor devices effectively so as to increase a packaging density of a three-dimensional structure thereof. In addition, wires (including the interconnecting portion) are formed in the resin so as to achieve the shortest wiring, providing a semiconductor device having a simple package structure.
In order to achieve the above-mentioned objects, there is also provided according to another aspect of the present invention a semiconductor device comprising:
a semiconductor element;
an external terminal used for an external connection;
an interposer having the semiconductor element mounted on a first surface thereof and having the external terminal formed on a second surface thereof opposite to the first surface so as to electrically connect the semiconductor element and the external terminal;
a resin sealing the semiconductor element on the first surface; and
an interconnecting portion formed on a surface of the semiconductor element within the resin, the interconnecting portion having a first connecting part electrically connected to the semiconductor element and having a second connecting part exposed on an outer surface of the resin.
According to the present invention, the interconnecting portion is formed on the surface of the semiconductor element with the first connecting part being electrically connected thereto so as to increase a degree of freedom in positioning the interconnecting portion.
Additionally, in the semiconductor device according to the present invention, the first connecting part and the second connecting part of the interconnecting portion may have different cross-sectional areas.
According to the present invention, the interconnecting portion can have a smaller total volume by forming one of the first connecting part and the second connecting part smaller than the other, and thus can have a smaller impedance. This increases an operating speed of the semiconductor device. Additionally, the interconnecting portion can be formed in a shorter time. Besides, a connection area between the first connecting part and the external terminal can be made large so as to make the semiconductor device more reliable.
Additionally, the semiconductor device according to the present invention may further comprise a bump formed on the second connecting part.
According to the present invention, the bump formed on the second connecting part increases a reliability in mounting the semiconductor device.
Additionally, the semiconductor device according to the present invention may further comprise a shield mounted on the second connecting part.
According to the present invention, the shield shields noises influencing the semiconductor device, and thus increases a reliability of the semiconductor device.
Additionally, the semiconductor device according to the present invention may further comprise an antenna mounted on the second connecting part.
According to the present invention, the antenna can be used for sending and receiving a radio signal. This enables the semiconductor device to provide a higher performance.
Additionally, the semiconductor device according to the present invention may further comprise an electronic component mounted on the second connecting part.
According to the present invention, an electronic component having various functions can be mounted on the second connecting part so as to increase the ability of the semiconductor device to provide a high performance and to serve a wide range of purposes.
Additionally, the semiconductor device according to the present invention may further comprise a heat sink mounted on the second connecting part.
Additionally, the semiconductor device according to the present invention may further comprise a second semiconductor element, a first surface thereof being connected to the first semiconductor element, and a heat sink mounted on a second surface of the second semiconductor element and the second connecting part.
According to the present invention, the heat sink can be mounted on the back of the semiconductor element and the second connecting part so as to effectively emit a heat generated in the semiconductor device. This enables the semiconductor device to be more reliable and to provide a higher performance.
In order to achieve the above-mentioned objects, there is also provided according to another aspect of the present invention a semiconductor device package comprising:
a plurality of semiconductor devices, each of the semiconductor devices having: a semiconductor element; an external terminal used for an external connection; an interposer having the semiconductor element mounted on a first surface thereof and having the external terminal formed on a second surface thereof opposite to the first surface so as to electrically connect the semiconductor element and the external terminal; a resin sealing the semiconductor element on the first surface; and an interconnecting portion formed within the resin, the interconnecting portion having a first connecting part electrically connected to the external terminal and having a second connecting part exposed on an outer surface of the resin,
wherein the semiconductor devices are stacked so that the second connecting part of one of the semiconductor devices is connected to the external terminal of another of the semiconductor devices located immediately above the one of the semiconductor devices.
According to the present invention, a plurality of the semiconductor devices of the same type can be stacked so as to decrease a volume of the semiconductor devices by providing a laminated structure. In other words, the semiconductor devices can have a three-dimensional structure so as to increase a packaging density thereof.
In order to achieve the above-mentioned objects, there is also provided according to another aspect of the present invention a method of manufacturing a semiconductor device, the method comprising the steps of:
arranging a semiconductor element on a surface of a substrate having an electrode pattern;
connecting the semiconductor element and the electrode pattern electrically;
forming a mask on the surface of the substrate, the mask having an interconnection hole at a position corresponding to the electrode pattern, so as to introduce a conductive material into the interconnection hole to form an interconnecting portion on the electrode pattern; and
forming a resin on the surface of the substrate after removing the mask so as to seal the semiconductor element and a part of the interconnecting portion, the other part of the interconnecting portion being exposed outward.
According to the present invention, a semiconductor device that can be stacked together with other semiconductor devices of the same type can be manufactured effectively.
In order to achieve the above-mentioned objects, there is also provided according to another aspect of the present invention a method of manufacturing a semiconductor device, the method comprising the steps of:
arranging a semiconductor element on a surface of a substrate having an electrode pattern;
connecting the semiconductor element and the electrode pattern electrically;
forming a resin on the surface of the substrate so as to seal the semiconductor element, the resin having an interconnection hole formed on the electrode pattern; and
introducing a conductive material into the interconnection hole so as to form an interconnecting portion within the resin.
According to the present invention, a semiconductor device that can be stacked together with other semiconductor devices of the same type can be manufactured effectively.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.